Genus Scaptognathides Monniot, 1972

Type: Scaptognathides planus Monniot 1972

Diagnosis. Idiosoma flattened. AD and PD large, OC much smaller. PD with 2 pairs of Glps. Dorsum with 6 pairs of setae. Adanal setae present on anal plate. GA with Pgs. Sgs present on GS. Gnathosoma length equalling a half of idiosomal length. Rostrum slender, parallel-sided, with a pair of maxillary setae on the base. Palpi 2- segmented (P-2, P-3, and P-4 fused into a single segment), separated from each other by more than width of P-1. P-2 with a seta on basal portion and 4 spurs on apical portion. Leg I distinctly larger than the other legs. Legs without distinct Bp setae. Lc I with umbrella-like arranged tines. Lc II–IV each crescent-like, sometimes with accessory process and/ or tines on the shaft forming a comb. Median claw undeveloped. The general structures of the genus is schematically shown in Fig. 6.

Remarks. The genus is similar to Scaptognathus in general appearance, but distinguishable from the latter by having slender, parallel-sided rostrum and umbrella-like claw of Ta I. The genus is marine arenicolous and recorded from tropical or warm-temperate sea areas ranged between 35°N and 35°S. This distributional range generally coincides with the area of which surface water temperature is more than 20°C and the integrated primary production is less than 0.06 mg chlorophyll m-3 (Longhurst 1998). This distributional range accords well with the coral reef distributions.

References. Abé (2011), Bartsch (2006b, 2009b), Longhurst (1998), Monniot (1972).